Fructose and NAFLD: The Multifaceted Aspects of Fructose Metabolism

Prophylactic effects of nutrition, dietary strategies, exercise, lifestyle and environment on nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease and its prevalence has risen sharply. However, whether nutrition, dietary strategies, exercise, lifestyle and environment have preventive value for NAFLD remains unclear.

METHODS

Through searching 4 databases (PubMed, Web of Science, Embase and the Cochrane Library) from inception to January 2025, we selected studies about nutrition, dietary strategies, exercise, lifestyle and environment in the prevention of NAFLD and conducted a narrative review on this topic.

RESULTS

Reasonable nutrient intake encompassing macronutrients and micronutrients have an independent protective relationship with NAFLD. Besides, proper dietary strategies including mediterranean diet, intermittent fasting diet, ketogenic diet, and dietary approaches to stop hypertension diet have their inhibitory effects on the developmental process of NAFLD. Moreover, right exercises including walking, jogging, bicycling, and swimming are recommended for the prevention of NAFLD because they could effectively reduce weight, which is an important risk factor for NAFLD, and improve liver function. In addition, embracing a healthy lifestyle including reducing sedentary behavior, not smoking, sleeping well and brushing teeth regularly is integral since it not only could reduce the risk of NAFLD but also significantly contribute to overall prevention and control. Finally, the environment, including the social and natural environments, plays a potential role in NAFLD prevention.

CONCLUSION

Nutrition, dietary strategies, exercise, lifestyle and environment play an important role in the prevention of NAFLD. Moreover, this review offers comprehensive prevention recommendations for people at high risk of NAFLD.

Unraveling MASLD: The Role of Gut Microbiota, Dietary Modulation, and AI-Driven Lifestyle Interventions

Gut microbiota has a crucial role in the pathophysiology of metabolic-associated steatotic liver disease (MASLD), influencing various metabolic mechanisms and contributing to the development of the disease. Dietary interventions targeting gut microbiota have shown potential in modulating microbial composition and mitigating MASLD progression. In this context, the integration of multi-omics analysis and artificial intelligence (AI) in personalized nutrition offers new opportunities for tailoring dietary strategies based on individual microbiome profiles and metabolic responses. The use of chatbots and other AI-based health solutions offers a unique opportunity to democratize access to health interventions due to their low cost, accessibility, and scalability. Future research should focus on the clinical validation of AI-powered dietary strategies, integrating microbiome-based therapies and precision nutrition approaches. Establishing standardized protocols and ethical guidelines will be crucial for implementing AI in MASLD management, paving the way for a more personalized, data-driven approach to disease prevention and treatment.

From Childhood Obesity to Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) and Hyperlipidemia Through Oxidative Stress During Childhood

BACKGROUND/OBJECTIVES

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is rapidly becoming the most prevalent form of chronic liver disease in both pediatric and adult populations. It encompasses a wide spectrum of liver abnormalities, ranging from simple fat accumulation to severe conditions such as inflammation, fibrosis, cirrhosis, and liver cancer. Major risk factors for MASLD include obesity, insulin resistance, type 2 diabetes, and hypertriglyceridemia.

METHODS

This narrative review employed a comprehensive search of recent literature to identify the latest studies on the relationship between MAFLD and obesity, the health consequences and the latest treatment options to prevent long-term damage to the liver and other organs. Additionally, the article presents perspectives on diagnostic biomarkers.

RESULTS

Childhood obesity is linked to a multitude of comorbid conditions and remains a primary risk factor for adult obesity. This abnormal fat accumulation is known to have long-term detrimental effects into adulthood. Scientific evidence unequivocally demonstrates the role of obesity-related conditions, such as insulin resistance, dyslipidemia, and hyperglycemia, in the development and progression of MASLD. Oxidative stress, stemming from mitochondrial dysfunction, is a leading factor in MASLD. This review discusses the interconnections between oxidative stress, obesity, dyslipidemia, and MASLD.

CONCLUSIONS

Atherogenic dyslipidemia, oxidative stress, inflammation, insulin resistance, endothelial dysfunction, and cytokines collectively contribute to the development of MASLD. Potential treatment targets for MASLD are focused on prevention and the use of drugs to address obesity and elevated blood lipid levels.

Mindful Eating: A Deep Insight Into Fructose Metabolism and Its Effects on Appetite Regulation and Brain Function

Fructose, a common sweetener in modern diets, has profound effects on both metabolism and brain function, primarily due to its distinct metabolic pathways. Unlike glucose, fructose bypasses critical regulatory steps in metabolism, particularly the phosphofructokinase-1 (PFK-1) feedback inhibition, leading to uncontrolled metabolism and increased fat storage. This review delves into the metabolic consequences of fructose consumption, including its limited role in directly stimulating insulin secretion, which affects satiety signaling and contributes to increased food intake. The small intestine initially helps metabolize ingested fructose, shielding the liver and brain from excessive exposure. However, when consumed in excess, particularly in diets high in processed foods, this protective mechanism becomes overwhelmed, contributing to metabolic disorders such as insulin resistance, obesity, and fatty liver disease. The review also explores fructose's impact on the brain, with a focus on the hippocampus, a key region for memory and learning. Chronic high fructose intake has been linked to mitochondrial dysfunction, increased production of reactive oxygen species (ROS), and neuroinflammation, all of which contribute to cognitive decline and impairments in memory and learning. Additionally, fructose-induced alterations in insulin signaling in the brain are associated with increased risk for neurodegenerative diseases. These findings underscore the potential long-term neurological consequences of excessive fructose intake and highlight the need for further human studies to assess the full spectrum of its effects on brain health. Addressing the rising consumption of fructose, particularly in processed foods, is essential for developing targeted strategies to mitigate its adverse metabolic and cognitive outcomes.

Mannose reduces fructose metabolism and reverses MASH in human liver slices and murine models in vivo

BACKGROUND

Fibrosis drives liver-related mortality in metabolic dysfunction-associated steatohepatitis (MASH), yet we have limited medical therapies to target MASH-fibrosis progression. Here we report that mannose, a simple sugar, attenuates MASH steatosis and fibrosis in 2 robust murine models and human liver slices.

METHODS

The well-validated fat-and-tumor MASH murine model for liver steatosis and fibrosis was employed. Mannose was supplied in the drinking water at the start ("Prevention" group) or at week 6 of the 12-week MASH regimen ("Therapy" group). The in vivo antifibrotic effects of mannose supplementation were tested in a second model of carbon tetrachloride (CCl4)-induced liver fibrosis. A quantitative and automated digital pathology approach was used to comprehensively assess steatosis and fibrosis phenotypes. Mannose was also tested in vitro in human and primary mouse hepatocytes conditioned with free fatty acids alone or with fructose, and human precision-cut liver slices from patients with end-stage MASH cirrhosis.

RESULTS

Oral mannose supplementation improved liver fibrosis in vivo in both fat-and-tumor MASH and CCl4 mouse models, as well as in human precision-cut liver slice MASH samples. Mannose also reduced liver steatosis in fat-and-tumor MASH mice, and in human and mouse hepatocytes in vitro. Ketohexokinase, the main enzyme in fructolysis, was decreased with mannose in whole mouse liver, cultured hepatocytes, and human precision-cut liver slices. Removal of fructose or overexpression of ketohexokinase each abrogated the antisteatotic effects of mannose.

CONCLUSIONS

This study identifies mannose as a novel therapeutic candidate for MASH that mitigates steatosis by dampening hepatocyte ketohexokinase expression and exerts independent antifibrotic effects in 2 mouse models and human liver tissue slices.

Fructose-induced progression of steatohepatitis involves disrupting aldolase B-AMPK signaling in methionine adenosyltransferase 1A deficient mice

OBJECTIVE

Aldolases (ALDO) are sensors that regulate AMPK via binding to fructose 1,6-biphosphate (FBP), an intermediate of glucose and fructose metabolism. Fructose consumption is linked to metabolic dysfunction-associated steatotic liver disease (MASLD) progression but whether ALDO-AMPK signaling is involved is unknown. Methionine adenosyltransferase alpha 1 (Mat1a) knockout (KO) mice have low hepatic S-adenosylmethionine (SAMe) level and spontaneously develop steatohepatitis. ALDOB methylation has not been reported and here we investigated whether SAMe level regulates ALDOB and ALDOB-AMPK signaling and whether fructose feeding accelerates MASLD progression by disrupting ALDOB-AMPK signaling.

METHODS

Mass spectrometry identified ALDOB methylation sites and recombinant in vitro approaches assessed how methylation at those sites affects ALDOB oligomerization and activity. Primary hepatocytes cultured with high/low glucose and/or fructose and wild type (WT) and Mat1a KO mice fed with a high-fructose diet examined AMPK-ALDOB signaling and MASLD progression.

RESULTS

In Mat1a KO livers ALDOB R173 is hypomethylated while ALDOB activity is enhanced. Recombinant ALDOB is methylated at R173 and R304 by protein arginine methyltransferase 1. Low hepatic SAMe level results in hypomethylated ALDOB, which favors the tetrameric form that has higher enzymatic activity, and higher capacity to signal to activate AMPK. Fructose, independently of glucose levels, inhibited AMPK activity and induced lipid accumulation in hepatocytes. Mat1a KO mice have hyperactivated AMPK and fructose feeding inhibits it, enhancing the accumulation of fat in the liver and the progression of MASLD.

CONCLUSION

Hepatic SAMe levels regulate ALDOB oligomeric state and enzymatic activity impacting on AMPK signaling and fructose-induced MASLD progression.

Dietary Influences on Gut Microbiota and Their Role in Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a major contributor to liver-related morbidity, cardiovascular disease, and metabolic complications. Lifestyle interventions, including diet and exercise, are first line in treating MASLD. Dietary approaches such as the low-glycemic-index Mediterranean diet, the ketogenic diet, intermittent fasting, and high fiber diets have demonstrated potential in addressing the metabolic dysfunction underlying this condition. The development and progression of MASLD are closely associated with taxonomic shifts in gut microbial communities, a relationship well-documented in the literature. Given the importance of diet as a primary treatment for MASLD, it is important to understand how gut microbiota and their metabolic byproducts mediate favorable outcomes induced by healthy dietary patterns. Conversely, microbiota changes conferred by unhealthy dietary patterns such as the Western diet may induce dysbiosis and influence steatotic liver disease through promoting hepatic inflammation, up-regulating lipogenesis, dysregulating bile acid metabolism, increasing insulin resistance, and causing oxidative damage in hepatocytes. Although emerging evidence has identified links between diet, microbiota, and development of MASLD, significant gaps remain in understanding specific microbial roles, metabolite pathways, host interactions, and causal relationships. Therefore, this review aims to provide mechanistic insights into the role of microbiota-mediated processes through the analysis of both healthy and unhealthy dietary patterns and their contribution to MASLD pathophysiology. By better elucidating the interplay between dietary nutrients, microbiota-mediated processes, and the onset and progression of steatotic liver disease, this work aims to identify new opportunities for targeted dietary interventions to treat MASLD efficiently.

Environmental toxicants modulate disease severity in pediatric metabolic dysfunction-associated steatohepatitis

OBJECTIVES

Metabolic dysfunction-associated steatotic liver disease (MASLD) is common in children. We hypothesized environmental toxins could drive progression to metabolic dysfunction-associated steatohepatitis (MASH), and assayed serum toxins and metabolites in children with histologically characterized MASLD/MASH.

METHODS

Environmental chemicals, common in household items, perfluoroalkyl substances (PFAS), polybrominated flame retardants (polybrominated diphenyl ethers [PBDEs]), and metabolic profiles were assayed in children enrolled in the multicenter NASH Clinical Research Network Pediatric Database 2. Mixture models, using repeated holdout weighted quantile sum regression (WQSrh) were run in addition to single chemical/metabolite logistic regression. For metabolomic analyses, random subset version of WQSrh was used for the large number of predictors versus participants. Nominal and false discovery rate (FDR) p-values (two-sided) were computed.

RESULTS

Four hundred and thirty-five children distributed across MASH (n = 293) and MASLD (n = 142), with 304 (69.9%) males. Mean (standard deviation) for Nonalcoholic Steatohepatitis Score (NAS) and alanine aminotransferase (ALT) for MASLD were 3.1 (1.0), 67.9 (43.4), and for MASH 4.2 (1.4), 144 (121). There was an inverse association between PFAS/PBDE mixture and MASH versus MASLD, lobular inflammation (p = 0.026), NAS (p = 0.009, FDR p = 0.04), and log-transformed ALT (p = 0.005, FDR p = 0.025) driven by perfluorohexane sulfonate (PFHXS). Metabolites from positive hydrophilic interaction liquid chromatography mode, biliverdin (p = 0.002) and 1-methylhistidine (associated with meat ingestion, p = 0.02) and reverse phase negative mode, hippuric acid (solvent exposure, p = 0.022) significantly associated with MASH.

CONCLUSIONS

Significant negative PFAS/PBDE mixture effect and odds of MASH were dominated by PHFXS. Several metabolites are significantly associated with MASH which inform mechanistic pathways and could drive key therapeutic and diagnostic strategies in children.

The role of the gut microbiome in the development of hepatobiliary cancers

Hepatobiliary cancers, including hepatocellular carcinoma and cancers of the biliary tract, share high mortality and rising incidence rates. They may also share several risk factors related to unhealthy western-type dietary and lifestyle patterns as well as increasing body weights and rates of obesity. Recent data also suggest a role for the gut microbiome in the development of hepatobiliary cancer and other liver pathologies. The gut microbiome and the liver interact bidirectionally through the "gut-liver axis," which describes the interactive relationship between the gut, its microbiota, and the liver. Here, we review the gut-liver interactions within the context of hepatobiliary carcinogenesis by outlining the experimental and observational evidence for the roles of gut microbiome dysbiosis, reduced gut barrier function, and exposure to inflammatory compounds as well as metabolic dysfunction as contributors to hepatobiliary cancer development. We also outline the latest findings regarding the impact of dietary and lifestyle factors on liver pathologies as mediated by the gut microbiome. Finally, we highlight some emerging gut microbiome editing techniques currently being investigated in the context of hepatobiliary diseases. Although much work remains to be done in determining the relationships between the gut microbiome and hepatobiliary cancers, emerging mechanistic insights are informing treatments, such as potential microbiota manipulation strategies and guiding public health advice on dietary/lifestyle patterns for the prevention of these lethal tumors.

The association of fructose and fiber consumption and physical activity with non-alcoholic fatty liver disease in children and adolescents: a cross-sectional study

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is emerging as the most prevalent liver disease in overweight and obese children. While no cure exists, dietary and lifestyle modifications have been shown to improve the condition. This study investigates the relationship between fructose and fiber consumption, physical activity, and NAFLD in children.

METHODS

A cross-sectional study was conducted on 378 overweight and obese children aged 6-13 years. NAFLD diagnosis was confirmed via ultrasound, and dietary intake was assessed using a 147-item food frequency questionnaire (FFQ). Physical activity was evaluated using the Modifiable Activity Questionnaire (MAQ). Multivariable logistic regression models were applied to determine the associations.

RESULTS

After excluding 53 participants due to incomplete data, 325 were included in the final analysis. The mean age was 9.2 ± 1.7 years, and 35% had NAFLD. No significant association was found between fructose intake and NAFLD (OR: 0.67, 95% CI: 0.35-1.29, P = 0.221). However, higher intake of legume fiber (OR: 0.48, 95% CI: 0.26-0.90, P = 0.03) and nut fiber (OR: 0.52, 95% CI: 0.28-0.95, P = 0.04) was significantly associated with a reduced risk of NAFLD. Physical activity showed a trend towards reduced NAFLD risk but was not statistically significant after adjustments (OR: 0.53, 95% CI: 0.22-1.04, P = 0.07).

CONCLUSIONS

While fructose intake was not significantly linked to NAFLD in this population, fiber from legumes and nuts appeared protective. Further prospective studies are needed to confirm these findings and clarify the role of physical activity in NAFLD prevention.

Berberine alleviates fructose-induced hepatic injury via ADK/AMPK/Nrf2 pathway: A novel insight

Berberine (BBR) is a major active component of traditional Chinese medicine Rhizoma Coptidis and Cortex Phellodendri, which have been frequently used to treat liver diseases. Oxidative stress and inflammation are two pivotal hepatic pathological hallmarks. This study aimed to explore the potential effect and underlying mechanism of BBR on fructose-induced rat liver injury model, and hepatocyte damage in HepG2 and BRL-3A cells. Our results indicated that BBR effectively reversed fructose-induced body weight gain, glucose intolerance, and insulin resistance, observably attenuated abnormal histopathological alterations and ameliorated serum activities of ALT and AST. In vivo and in vitro, BBR significantly alleviated the secretion of pro-inflammatory cytokines IL-6 and TNF-α, and elevated levels of anti-inflammatory cytokine IL-10. BBR also attenuated oxidative stress by markedly decreasing intracellular contents of ROS and MDA, and increasing SOD enzymatic activity and GSH level. Furthermore, BBR substantially upregulated the protein expression of Nrf2, HO-1 and p-AMPK, and the fluorescence level of p-AMPK. In addition, BBR significantly increased the level of AMP, the ratio of AMP/ATP, and promoted the expression of ADK. Nevertheless, siADK abolished the benefits exerted by BBR on HepG2 and BRL-3A cells. Conclusively, the hepatoprotective effect of BBR was believed to be intimately associated with anti-inflammatory and antioxidant action mediated, at least partially, via ADK/AMPK/Nrf2 signaling. This work provided further support for the traditional application of Rhizoma Coptidis and Cortex Phellodendri in liver protection and might shed novel dimension to the clinical application of BBR, providing a promising lead compound for drug design.

Lifestyle intervention for metabolic dysfunction-associated fatty liver disease: a 24-h integrated behavior perspective

INTRODUCTION

The prevalence, health and socioeconomic burden of metabolic dysfunction-associated fatty liver disease (MAFLD) is growing, increasing the need for novel evidence-based lifestyle approaches. Lifestyle is the cornerstone for MAFLD management and co-existing cardiometabolic dysfunction. The aim of this review was to evaluate the evidence for lifestyle management of MAFLD, with a specific lens on 24-hour integrated behaviour and provide practical recommendations for implementation of the evidence.

RESULTS

Weight loss ≥ 7-10% is central to lifestyle management; however, liver and cardiometabolic benefits are attainable with improved diet quality and exercise even without weight loss. Lifestyle intervention for MAFLD should consider an integrated '24-h' approach that is cognisant of diet, physical activity/exercise, sedentary behavior, smoking, alcohol intake and sleep. Dietary management emphasises energy deficit and improved diet quality, especially the Mediterranean diet, although sociocultural adaptations to meet preferences should be considered. Increasing physical activity and reducing sedentary behavior can prevent MAFLD, with strongest evidence in MAFLD supporting regular structured moderate-vigorous aerobic exercise for 150-240 min/week. Resistance training in addition to aerobic exercise should be considered and prioritised for those who are losing body mass via diet and/or pharmacological approaches and those with sarcopenia, to minimise bone and lean mass loss. Limited evidence suggests that sleep is important for MAFLD prevention. Emerging novel approaches to diet and exercise may address some of the key barriers to behaviour change (e.g. lack of time, access to resources and social support).

FUTURE DIRECTIONS

Large-scale multidisciplinary trials in people with MAFLD with long-term follow-up, that can be scaled up into mainstream healthcare, are required. Future management guidelines should consider the heterogeneity of MAFLD and specialised models of care that coordinate the health workforce to manage the increased and growing MAFLD population.

Dietary inflammation and vascular calcification: a comprehensive review of the associations, underlying mechanisms, and prevention strategies

Cardiovascular disease (CVD) is one of the leading causes of death globally, and vascular calcification (VC) has been recognized as an independent and strong predictor of global CVD and mortality. Chronic inflammation has been demonstrated to play a significant role in the progression of VC. This review aims to summarize the literature that aimed to elucidate the associations between dietary inflammation (DI) and VC as well as to explore the mechanisms underlying the association and discuss strategies (including dietary interventions) to prevent VC. Notably, diets rich in processed foods, carbohydrates with high glycemic index/load, saturated fatty acids, trans-fatty acids, cholesterol, and phosphorus were found to induce inflammatory responses and accelerate the progression of VC, indicating a close relationship between DI and VC. Moreover, we demonstrate that an imbalance in the composition of the gut microbiota caused by the intake of specific dietary choices favored the production of certain metabolites that may contribute to the progression of VC. The release of inflammatory and adhesion cytokines, activation of inflammatory pathways, oxidative stress, and metabolic disorders were noted to be the main mechanisms through which DI induced VC. To reduce and slow the progression of VC, emphasis should be placed on the intake of diets rich in omega-3 fatty acids, dietary fiber, Mg, Zn, and polyphenols, as well as the adjustment of dietary pattern to reduce the risk of VC. This review is expected to be useful for guiding future research on the interplay between DI and VC.

Interindividual Variability in Postprandial Plasma Fructose Patterns in Adults

High fructose consumption is associated with an increased risk of cardiometabolic disease, and fructose feeding dose-dependently induces markers reflective of poor metabolic health. However, unlike glucose, surprisingly little is known about person-to-person differences in postprandial plasma fructose patterns. Herein, we performed post hoc analyses of two published studies to address this question. In the first cohort, 16 participants' all-day plasma fructose concentration patterns (08:00-23:30) were determined (8 women and 8 men) while consuming mixed meals (breakfast, lunch, and dinner) with a fructose-sweetened beverage at each meal (30% of calories). Individually plotted results demonstrate remarkably disparate fructose patterns with respect to peak concentration and timing. A secondary study confirmed substantial interindividual variability in plasma fructose patterns over 240 min in 16 adults consuming Ensure®, a commercially available mixed macronutrient drink containing a low dose of fructose. The health ramifications of interindividual variations in postprandial fructose metabolism and the underlying physiological mechanisms driving differences in post-meal blood patterns remain to be explored. Future research is warranted to determine if interindividual variability in fructose digestion, metabolism, and postprandial blood concentration patterns is associated with cardiometabolic health phenotypes and disease risk.

Dietary fructose: from uric acid to a metabolic switch in pediatric metabolic dysfunction-associated steatotic liver disease

Fructose consumption in pediatric subjects is rising, as the prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH). Despite increasing evidence supporting the detrimental effects of fructose in the development of Metabolic Syndrome (MetS) and its related comorbidities, the association between fructose intake and liver disease remains unclear, mainly in youths. The current narrative review aims to illustrate the correlation between fructose metabolism and liver functions besides its impact on obesity and MASLD in pediatrics. Fructose metabolism is involved in the liver through the classical lipogenic pathway via de novo lipogenesis (DNL) or in the alternative pathway via uric acid accumulation. Hyperuricemia is one of the main features of MALSD patients, underlining how uric acid is growing interest as a new marker of disease. Observational and interventional studies conducted in children and adolescents, who consumed large amounts of fructose and glucose in their diet, were included. Most of these studies emphasized the association between high fructose intake and weight gain, dyslipidemia, insulin resistance, and MASLD/MASH, even in normal-weight children. Conversely, reducing fructose intake ameliorates liver fat accumulation, lipid profile, and weight. In conclusion, fructose seems a potent inducer of both insulin resistance and hepatic fat accumulation.

Beneficial Effects of the Ketogenic Diet on Nonalcoholic Fatty Liver Disease (NAFLD/MAFLD)

The prevalence of nonalcoholic fatty liver disease (NAFLD) is likely to be approaching 38% of the world's population. It is predicted to become worse and is the main cause of morbidity and mortality due to hepatic pathologies. It is particularly worrying that NAFLD is increasingly diagnosed in children and is closely related, among other conditions, to insulin resistance and metabolic syndrome. Against this background is the concern that the awareness of patients with NAFLD is low; in one study, almost 96% of adult patients with NAFLD in the USA were not aware of their disease. Thus, studies on the therapeutic tools used to treat NAFLD are extremely important. One promising treatment is a well-formulated ketogenic diet (KD). The aim of this paper is to present a review of the available publications and the current state of knowledge of the effect of the KD on NAFLD. This paper includes characteristics of the key factors (from the point of view of NAFLD regression), on which ketogenic diet exerts its effects, i.e., reduction in insulin resistance and body weight, elimination of fructose and monosaccharides, limitation of the total carbohydrate intake, anti-inflammatory ketosis state, or modulation of gut microbiome and metabolome. In the context of the evidence for the effectiveness of the KD in the regression of NAFLD, this paper also suggests the important role of taking responsibility for one's own health through increasing self-monitoring and self-education.

Common Denominator of MASLD and Some Non-Communicable Diseases

Currently, steatohepatitis has been designated as metabolic dysfunction-associated steatohepatitis (MASLD). MASLD risk factors mainly include metabolic disorders but can also include genetic, epigenetic, and environmental factors. Disease entities such as obesity, diabetes, cardiovascular disease, and MASLD share similar pathomechanisms and risk factors. Moreover, a bidirectional relationship is observed between the occurrence of certain chronic diseases and MASLD. These conditions represent a global public health problem that is responsible for poor quality of life and high mortality. It seems that paying holistic attention to these problems will not only help increase the chances of reducing the incidence of these diseases but also assist in the prevention, treatment, and support of patients.

Implications of Microbiota and Immune System in Development and Progression of Metabolic Dysfunction-Associated Steatotic Liver Disease

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent type of liver disease worldwide. The exact pathophysiology behind MASLD remains unclear; however, it is thought that a combination of factors or "hits" act as precipitants for disease onset and progression. Abundant evidence supports the roles of diet, genes, metabolic dysregulation, and the intestinal microbiome in influencing the accumulation of lipids in hepatocytes and subsequent progression to inflammation and fibrosis. Currently, there is no cure for MASLD, but lifestyle changes have been the prevailing cornerstones of management. Research is now focusing on the intestinal microbiome as a potential therapeutic target for MASLD, with the spotlight shifting to probiotics, antibiotics, and fecal microbiota transplantation. In this review, we provide an overview of how intestinal microbiota interact with the immune system to contribute to the pathogenesis of MASLD and metabolic dysfunction-associated steatohepatitis (MASH). We also summarize key microbial taxa implicated in the disease and discuss evidence supporting microbial-targeted therapies in its management.

Does Resveratrol Improve Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)?

Metabolic dysfunction-associated steatotic liver disease (MASLD) is influenced by a variety of factors, including environmental and genetic factors. The most significant outcome is the alteration of free fatty acid and triglyceride metabolism. Lipotoxicity, impaired autophagy, chronic inflammation, and oxidative stress, as well as coexisting insulin resistance, obesity, and changes in the composition of gut microbiota, are also considered crucial factors in the pathogenesis of MASLD. Resveratrol is a polyphenolic compound that belongs to the stilbene subgroup. This review summarises the available information on the therapeutic effects of resveratrol against MASLD. Resveratrol has demonstrated promising antisteatotic, antioxidant, and anti-inflammatory activities in liver cells in in vitro and animal studies. Resveratrol has been associated with inhibiting the NF-κB pathway, activating the SIRT-1 and AMPK pathways, normalizing the intestinal microbiome, and alleviating intestinal inflammation. However, clinical studies have yielded inconclusive results regarding the efficacy of resveratrol in alleviating hepatic steatosis or reducing any of the parameters found in MASLD in human patients. The lack of homogeneity between studies, low bioavailability of resveratrol, and population variability when compared to animal models could be the reasons for this.

Underlying Mechanisms behind the Brain-Gut-Liver Axis and Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Metabolic-associated fatty liver disease (MAFLD) includes several metabolic dysfunctions caused by dysregulation in the brain-gut-liver axis and, consequently, increases cardiovascular risks and fatty liver dysfunction. In MAFLD, type 2 diabetes mellitus, obesity, and metabolic syndrome are frequently present; these conditions are related to liver lipogenesis and systemic inflammation. This study aimed to review the connection between the brain-gut-liver axis and MAFLD. The inflammatory process, cellular alterations in hepatocytes and stellate cells, hypercaloric diet, and sedentarism aggravate the prognosis of patients with MAFLD. Thus, to understand the modulation of the physiopathology of MAFLD, it is necessary to include the organokines involved in this process (adipokines, myokines, osteokines, and hepatokines) and their clinical relevance to project future perspectives of this condition and bring to light new possibilities in therapeutic approaches. Adipokines are responsible for the activation of distinct cellular signaling in different tissues, such as insulin and pro-inflammatory cytokines, which is important for balancing substances to avoid MAFLD and its progression. Myokines improve the quantity and quality of adipose tissues, contributing to avoiding the development of MAFLD. Finally, hepatokines are decisive in improving or not improving the progression of this disease through the regulation of pro-inflammatory and anti-inflammatory organokines.

Non-Necroptotic Roles of MLKL in Diet-Induced Obesity, Liver Pathology, and Insulin Sensitivity: Insights from a High-Fat, High-Fructose, High-Cholesterol Diet Mouse Model

Chronic inflammation is a key player in metabolic dysfunction-associated fatty liver disease (MAFLD) progression. Necroptosis, an inflammatory cell death pathway, is elevated in MAFLD patients and mouse models, yet its role is unclear due to the diverse mouse models and inhibition strategies. In our study, we inhibited necroptosis by targeting mixed lineage kinase domain-like pseudokinase (MLKL), the terminal effector of necroptosis, in a high-fat, high-fructose, high-cholesterol (HFHFrHC) mouse model of diet-induced MAFLD. Despite the HFHFrHC diet upregulating MLKL (2.5-fold), WT mice livers showed no increase in necroptosis markers or associated proinflammatory cytokines. Surprisingly, Mlkl-/- mice experienced exacerbated liver inflammation without protection from diet-induced liver damage, steatosis, or fibrosis. In contrast, Mlkl+/- mice showed a significant reduction in these parameters that was associated with elevated Pparα and Pparγ levels. Both Mlkl-/- and Mlkl+/- mice on the HFHFrHC diet resisted diet-induced obesity, attributed to the increased beiging, enhanced oxygen consumption, and energy expenditure due to adipose tissue, and exhibited improved insulin sensitivity. These findings highlight the tissue-specific effects of MLKL on the liver and adipose tissue, and they suggest a dose-dependent effect of MLKL on liver pathology.

Mannose Supplementation Curbs Liver Steatosis and Fibrosis in Murine MASH by Inhibiting Fructose Metabolism

Metabolic dysfunction-associated steatohepatitis (MASH) can progress to cirrhosis and liver cancer. There are no approved medical therapies to prevent or reverse disease progression. Fructose and its metabolism in the liver play integral roles in MASH pathogenesis and progression. Here we focus on mannose, a simple sugar, which dampens hepatic stellate cell activation and mitigates alcoholic liver disease in vitro and in vivo . In the well-validated FAT-MASH murine model, oral mannose supplementation improved both liver steatosis and fibrosis at low and high doses, whether administered either at the onset of the model ("Prevention") or at week 6 of the 12-week MASH regimen ("Reversal"). The in vivo anti-fibrotic effects of mannose supplementation were validated in a second model of carbon tetrachloride-induced liver fibrosis. In vitro human and mouse primary hepatocytes revealed that the anti-steatotic effects of mannose are dependent on the presence of fructose, which attenuates expression of ketohexokinase (KHK), the main enzyme in fructolysis. KHK is decreased with mannose supplementation in vivo and in vitro, and overexpression of KHK abrogated the anti-steatotic effects of mannose. Our study identifies mannose as a simple, novel therapeutic candidate for MASH that mitigates metabolic dysregulation and exerts anti-fibrotic effects.

Nutrition assessment and MASH severity in children using the Healthy Eating Index

BACKGROUND

Pediatric metabolic-associated fatty liver disease (MAFLD) is a global health problem, with lifestyle modification as its major therapeutic strategy. Rigorous characterization of dietary content on MAFLD in children is lacking. We hypothesized an objectively measured healthier diet would positively modulate MAFLD.

METHODS

Diet was assessed using the Nutrition Data System for Research in children enrolled from 10 tertiary clinical centers to determine the Healthy Eating Index (HEI, 0-100) and individual food components.

RESULTS

In all, 119 children were included (13.3 ± 2.7 y), 80 (67%) male, 67 (18%) White, and 90 (76%) Hispanic, with an average body mass index Z-score of 2.2 ± 0.5. Diet was classified as low HEI < 47.94 (n = 39), mid HEI ≥ 47.94 and < 58.89 (n = 41), or high HEI ≥ 58.89 (n=39). Children with high HEI (healthier diet) had lower body weight (p = 0.005) and more favorable lipids. Mean serum triglycerides for low, mid, and high HEI were 163, 148, and 120 mg/dL, respectively; p = 0.04 mid versus high, p = 0.01 low versus high. Mean HDL was 38, 41 and 43 mg/dL; p = 0.02 low vs high. Less severe steatosis was noted with added sugar ≤ 10% of calories (p = 0.03). Higher lobular inflammation is associated with a higher percentage of calories from fat (OR (95% CI) = 0.95 (0.91-1.00), p = 0.04).

CONCLUSIONS

In children with MAFLD, high HEI is associated with lower body weight and more favorable lipids, while added sugar and fat intake has individual histologic features. Differential consumption of major dietary components may modify both metabolic risk factors and histologic liver injury, highlighting the importance of objective diet assessments in children with MAFLD.

Pathomechanisms of Diabetic Kidney Disease

The worldwide occurrence of diabetic kidney disease (DKD) is swiftly rising, primarily attributed to the growing population of individuals affected by type 2 diabetes. This surge has been transformed into a substantial global concern, placing additional strain on healthcare systems already grappling with significant demands. The pathogenesis of DKD is intricate, originating with hyperglycemia, which triggers various mechanisms and pathways: metabolic, hemodynamic, inflammatory, and fibrotic which ultimately lead to renal damage. Within each pathway, several mediators contribute to the development of renal structural and functional changes. Some of these mediators, such as inflammatory cytokines, reactive oxygen species, and transforming growth factor β are shared among the different pathways, leading to significant overlap and interaction between them. While current treatment options for DKD have shown advancement over previous strategies, their effectiveness remains somewhat constrained as patients still experience residual risk of disease progression. Therefore, a comprehensive grasp of the molecular mechanisms underlying the onset and progression of DKD is imperative for the continued creation of novel and groundbreaking therapies for this condition. In this review, we discuss the current achievements in fundamental research, with a particular emphasis on individual factors and recent developments in DKD treatment.

6-Methyl flavone inhibits Nogo-B expression and improves high fructose diet-induced liver injury in mice

Excessive fructose consumption increases hepatic de novo lipogenesis, resulting in cellular stress, inflammation and liver injury. Nogo-B is a resident protein of the endoplasmic reticulum that regulates its structure and function. Hepatic Nogo-B is a key protein in glycolipid metabolism, and inhibition of Nogo-B has protective effects against metabolic syndrome, thus small molecules that inhibit Nogo-B have therapeutic benefits for glycolipid metabolism disorders. In this study we tested 14 flavones/isoflavones in hepatocytes using dual luciferase reporter system based on the Nogo-B transcriptional response system, and found that 6-methyl flavone (6-MF) exerted the strongest inhibition on Nogo-B expression in hepatocytes with an IC50 value of 15.85 μM. Administration of 6-MF (50 mg· kg-1 ·d-1, i.g. for 3 weeks) significantly improved insulin resistance along with ameliorated liver injury and hypertriglyceridemia in high fructose diet-fed mice. In HepG2 cells cultured in a media containing an FA-fructose mixture, 6-MF (15 μM) significantly inhibited lipid synthesis, oxidative stress and inflammatory responses. Furthermore, we revealed that 6-MF inhibited Nogo-B/ChREBP-mediated fatty acid synthesis and reduced lipid accumulation in hepatocytes by restoring cellular autophagy and promoting fatty acid oxidation via the AMPKα-mTOR pathway. Thus, 6-MF may serve as a potential Nogo-B inhibitor to treat metabolic syndrome caused by glycolipid metabolism dysregulation.

Ketohexokinase-dependent metabolism of cerebral endogenous fructose in microglia drives diabetes-associated cognitive dysfunction

Dementia, as an advanced diabetes-associated cognitive dysfunction (DACD), has become the second leading cause of death among diabetes patients. Given that little guidance is currently available to address the DACD process, it is imperative to understand the underlying mechanisms and screen out specific therapeutic targets. The excessive endogenous fructose produced under high glucose conditions can lead to metabolic syndrome and peripheral organ damage. Although generated by the brain, the role of endogenous fructose in the exacerbation of cognitive dysfunction is still unclear. Here, we performed a comprehensive study on leptin receptor-deficient T2DM mice and their littermate m/m mice and revealed that 24-week-old db/db mice had cognitive dysfunction and excessive endogenous fructose metabolism in the hippocampus by multiomics analysis and further experimental validation. We found that the rate-limiting enzyme of fructose metabolism, ketohexokinase, is primarily localized in microglia. It is upregulated in the hippocampus of db/db mice, which enhances mitochondrial damage and reactive oxygen species production by promoting nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) expression and mitochondrial translocation. Inhibiting fructose metabolism via ketohexokinase depletion reduces microglial activation, leading to the restoration of mitochondrial homeostasis, recovery of structural synaptic plasticity, improvement of CA1 pyramidal neuron electrophysiology and alleviation of cognitive dysfunction. Our findings demonstrated that enhanced endogenous fructose metabolism in microglia plays a dominant role in diabetes-associated cognitive dysfunction and could become a potential target for DACD.

Glucoregulatory effect of butyrate is associated with elevated circulating VEGF and reduced cardiac lactate in high fructose fed rats

Background

High fructose diet has been linked with impaired body metabolism and cardiovascular diseases. Sodium butyrate (NaB) was documented to improve glucoregulation and cardiometabolic problems associated with high fructose diet (HFrD) but the mechanisms behind it are unclear. As a result, the purpose of this study was to look into the effects of NaB on VEGF and cardiac lactate in HFrD-induced dysmetabolism.

Methods

Twenty male Wistar rats of weight 130-140 g were assigned randomly after a week of acclimation into four groups: Control diet (CTR), High fructose drink (HFrD); 10 % (w/v), NaB (200 mg/kg bw), and HFrD + NaB (200 mg/kg bw). The animals were induced to be unconscious with 50 mg/kg of pentobarbital sodium intraperitoneally, blood samples were taken via cardiac puncture and cardiac tissue homogenates were obtained for Fasting Blood Sugar (FBS) and plasma insulin, cardiac glycogen, plasma and cardiac glycogen synthase, plasma and cardiac nitric oxide as well as vascular endothelial growth factor (VEGF).

Result

HFrD resulted in statistical elevation body and cardiac weight, plasma glucose, plasma insulin, cardiac lactate, glycogen and decreased nitric oxide level (NO) when compared with the control group. Administration of NaB reduced cardiac weight, blood glucose, plasma insulin, cardiac lactate while nitric oxide and glycogen increased (P < 0.05). NaB increased plasma glycogen synthase in normal rats, plasma and cardiac circulating VEGF in HFrD administered rats (P < 0.05) while no change was produced in plasma and cardiac glycogen synthase level of HFrD treated rats.

Conclusion

Sodium butyrate improves glucoregulation by reducing cardiac lactate and increasing circulating VEGF in HFrD-treated rats.

Non-alcoholic fatty liver disease in women - Current knowledge and emerging concepts

Non-alcoholic fatty liver disease (NAFLD) is a major cause of liver disease worldwide, affecting up to 30% of adults. Progression to non-alcoholic steatohepatitis (NASH) is a key risk factor for cirrhosis, hepatocellular carcinoma and cardiovascular events. Alterations in reproductive hormones are linked to the development and/or progression of NAFLD/NASH in women. Women with polycystic ovary syndrome and those with oestrogen deficiency are at increased risk of NAFLD/NASH, with higher mortality rates in older women compared to men of similar ages. NAFLD/NASH is currently the leading indication for liver transplantation in women without hepatocellular carcinoma. Therefore, a better understanding of NAFLD in women is needed to improve outcomes. In this review, we discuss the hormonal and non-hormonal factors that contribute to NAFLD development and progression in women. Furthermore, we highlight areas of focus for clinical practice and for future research.

Acetyl-11-Keto-Beta-Boswellic Acid Has Therapeutic Benefits for NAFLD Rat Models That Were Given a High Fructose Diet by Ameliorating Hepatic Inflammation and Lipid Metabolism

Acetyl-11-keto-beta-boswellic acid (AKBA), a potent anti-inflammatory compound purified from Boswellia species, was investigated in a preclinical study for its potential in preventing and treating non-alcoholic fatty liver disease (NAFLD), the most common chronic inflammatory liver disorder. The study involved thirty-six male Wistar rats, equally divided into prevention and treatment groups. In the prevention group, rats were given a high fructose diet (HFrD) and treated with AKBA for 6 weeks, while in the treatment group, rats were fed HFrD for 6 weeks and then given a normal diet with AKBA for 2 weeks. At the end of the study, various parameters were analyzed including liver tissues and serum levels of insulin, leptin, adiponectin, monocyte chemoattractant protein-1 (MCP-1), transforming growth factor beta (TGF-β), interferon gamma (INF-ϒ), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). Additionally, the expression levels of genes related to the inflammasome complex and peroxisome proliferator-activated receptor gamma (PPAR-ϒ), as well as the levels of phosphorylated and non-phosphorylated AMP-activated protein kinase alpha-1 (AMPK-α1) protein, were measured. The results showed that AKBA improved NAFLD-related serum parameters and inflammatory markers and suppressed PPAR-ϒ and inflammasome complex-related genes involved in hepatic steatosis in both groups. Additionally, AKBA prevented the reduction of the active and inactive forms of AMPK-α1 in the prevention group, which is a cellular energy regulator that helps suppress NAFLD progression. In conclusion, AKBA has a beneficial effect on preventing and avoiding the progression of NAFLD by preserving lipid metabolism, improving hepatic steatosis, and suppressing liver inflammation.

Association of food intake with a risk of metabolic dysfunction-associated fatty liver disease: a cross-sectional study

Background

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a common liver disease, the risk of which can be increased by poor diet. The objective of this study was to evaluate the associations between food items and MAFLD, and to propose reasonable dietary recommendations for the prevention of MAFLD.

Methods

Physical examination data were collected from April 2015 through August 2017 at Nanping First Hospital (n = 3,563). Dietary intakes were assessed using a semi-quantitative food frequency questionnaire. The association between food intake and the risk of MAFLD was assessed by using the inverse probability weighted propensity score.

Results

Beverages (soft drinks and sugar-sweetened beverages) and instant noodles were positively associated with MAFLD risk, adjusting for smoking, drinking, tea intake, and weekly hours of physical activity [adjusted odds ratio (ORadjusted): 1.568; P = 0.044; ORadjusted: 4.363; P = 0.001]. Milk, tubers, and vegetables were negatively associated with MAFLD risk (ORadjusted: 0.912; P = 0.002; ORadjusted: 0.633; P = 0.007; ORadjusted: 0.962; P = 0.028). In subgroup analysis, the results showed that women [odds ratio (OR): 0.341, 95% confidence interval (CI): 0.172-0.676] had a significantly lower risk of MAFLD through consuming more tubers than men (OR: 0.732, 95% CI: 0.564-0.951).

Conclusions

These findings suggest that reducing consumption of beverages (soft drinks and sugar-sweetened beverages) and instant noodles, and consuming more milk, vegetables, and tubers may reduce the risk of MAFLD.

Gut commensal Kineothrix alysoides mitigates liver dysfunction by restoring lipid metabolism and gut microbial balance

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as Non-Alcoholic Fatty Liver Disease, is a widespread liver condition characterized by excessive fat buildup in hepatocytes without significant alcohol consumption. Manipulation of the gut microbiome has been considered to prevent and improve the occurrence and progression of MASLD, particularly through the gut-liver axis. This study aimed to investigate the correlation between the gut microbiome and liver function and determine whether the gut microbiome can ameliorate MASLD. We comparatively analyzed the gut microbiome composition between mice fed normal chow and those fed a high-fat diet and observed that the abundance of Kineothrix alysoides decreased in the high-fat group. Further analysis showed that treatment with K. alysoides in the high-fat diet group led to decreased weight loss, and MASLD attenuation. Importantly, K. alysoides treatment attenuated MASLD in mice fed a high-fat, high-fructose diet (HFHF), which can cause advanced liver damage. Furthermore, administration of K. alysoides altered the gut microbial composition in the HFHF diet group and improved MASLD. Overall, these findings demonstrate the potential of K. alysoides in restoring gut health and facilitating lipid metabolism to prevent and treat MASLD.

The intestinal-hepatic axis: a comprehensive review on fructose metabolism and its association with mortality and chronic metabolic diseases

Fructose is a common ingredient of food industry in the form of sucrose and high fructose corn sirup (HFCS). Due to its unique metabolic properties, excessive intake of fructose has been linked to various diseases, including obesity, nonalcoholic fatty liver disease (NAFLD), cardiovascular disease (CVD), chronic renal insufficiency, and even increase the risk of death. Interestingly, although high fructose intake may induce gout, it does not cause hyperuricemia, and the underlying molecular mechanisms remain debated. While previous studies focused on the liver as the primary site of fructose metabolism, recent evidence has suggested a crucial role for the intestine-hepatic axis in fructose metabolism. Low dose fructose is mainly metabolized in the small intestine. Only when the intake exceeds the intestine's metabolic capacity fructose spills over to be metabolized in the liver. High fructose diets also have a significant impact on the diversity of the gut microbiota, leading to alterations in the metabolic byproducts produced by these gut bacteria and thereby inducing endotoxemia. This paper provides a comprehensive review of the epidemiological and pathological studies conducted in recent years, describing the metabolic differences between fructose and glucose and the possible mechanisms underlying the link between excessive fructose intake and chronic metabolic diseases.

The Lasting Effects of COVID-19 on the Progression of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

It is estimated that around 30% of the population living in Western countries has metabolic dysfunction-associated steatotic liver disease (MASLD), a spectrum of pathology (not attributed to alcohol/substance intake) initiated by steatosis and progression toward inflammation and irreversible fibrosis metabolic dysfunction-associated steatohepatitis (MASH). With inflammation being a key component of the transition to MASH, it raises the question of whether the ongoing COVID-19 pandemic, which has notoriously induced hyperinflammatory states, may influence the progression of MASLD. Specifically, it remains unclear if the potential chronic sequelae of COVID-19 in patients who recovered from it may increase the predisposition for MASH. Since MASH maintains a high risk for hepatocellular carcinoma, liver failure, and the need for a liver transplant, the potential additive effects of COVID-19 could prove critical to study. Thus, the objective of this study was to conduct a literature review to examine if COVID-19 could have chronic sequelae that affect the progression of MASLD pathogenesis. It was hypothesized that severe cases of COVID-19 could induce systemic inflammation, metabolic changes, and lasting gut microbiome alterations that lead to inflammatory and fibrotic changes in the liver, similar to those seen in MASH. A scoping review of the literature was conducted utilizing the PubMed database. Studies that examined hepatobiliary pathology, gut microbiome, systemic inflammation, metabolic changes, drug-induced liver injury (DILI), and hypoxia seen in COVID-19 were included. Human studies of adult cohorts, animal models, and in vitro experiments were included. Genetic components of MASLD were not examined. Exclusion criteria also encompassed any studies not referencing the hepatobiliary, gastrointestinal tract, portal system, or systemic circulation. Findings indicated a frequent trend of elevated liver enzymes, mild steatosis, Kupffer cell hyperplasia, and hepatobiliary congestion. It was found that direct cytopathic effects on hepatocytes were unlikely, but the direct viral insult of cholangiocytes was a potential complication. High serum levels of IL-1, TNF-a, and MCP-1, in COVID-19 were found as potential risk factors for MASH development. Hypoxia, altered lipid metabolism, and iatrogenic DILI were also proposed as potential precipitators of MASH development. Notably, lasting changes in gut microbiome were also frequently observed and correlated closely with those seen in MASH.

Bacteriophage targeting microbiota alleviates non-alcoholic fatty liver disease induced by high alcohol-producing Klebsiella pneumoniae

Our previous studies have shown that high alcohol-producing Klebsiella pneumoniae (HiAlc Kpn) in the intestinal microbiome could be one of the causes of non-alcoholic fatty liver disease (NAFLD). Considering antimicrobial resistance of K. pneumoniae and dysbacteriosis caused by antibiotics, phage therapy might have potential in treatment of HiAlc Kpn-induced NAFLD, because of the specificity targeting the bacteria. Here, we clarified the effectiveness of phage therapy in male mice with HiAlc Kpn-induced steatohepatitis. Comprehensive investigations including transcriptomes and metabolomes revealed that treatment with HiAlc Kpn-specific phage was able to alleviate steatohepatitis caused by HiAlc Kpn, including hepatic dysfunction and expression of cytokines and lipogenic genes. In contrast, such treatment did not cause significantly pathological changes, either in functions of liver and kidney, or in components of gut microbiota. In addition to reducing alcohol attack, phage therapy also regulated inflammation, and lipid and carbohydrate metabolism. Our data suggest that phage therapy targeting gut microbiota is an alternative to antibiotics, with potential efficacy and safety, at least in HiAlc Kpn-caused NAFLD.

Diet and metabolic syndrome: a narrative review

Metabolic syndrome (MetS) is a highly prevalent condition defined by the presence of at least three out of five risk factors including central obesity, increased fasting glucose, high blood pressure, and dyslipidaemia. Metabolic syndrome is associated with a 2-fold increase in cardiovascular outcomes and a 1.5-fold increase in all-cause mortality. Excess energy intake and Western dietary pattern may influence the development of metabolic syndrome. By contrast, both Mediterranean diet (Med-diet) and Dietary Approaches to Stop Hypertension (DASH) diet, with or without calorie restriction, have positive effects. For the prevention and management of MetS, it is recommended to increase the daily intake of fiber-rich and low-glycaemic-index foods and the consumption of fish and dairy products, especially yogurt and nuts. Moreover, it is advisable to consume a large variety of unprocessed cereals, legumes, and fruit. Finally, it is suggested to replace saturated fatty acids with monounsaturated and polyunsaturated fatty acids and to limit the consumption of free sugars to less than 10% of the total energy intake. The aim of this narrative review is to analyze current evidence on the different dietary patterns and nutrients that may affect prevention and treatment of MetS and to discuss the underlying pathophysiological mechanisms.

Non-Alcoholic Fatty Liver Disease, Atherosclerosis, and Cardiovascular Disease in Asia

The prevalence of non-alcoholic fatty liver disease (NAFLD) is estimated to increase to over half of the adult population by 2040 globally. Since the final diagnosis of NAFLD is made by a liver biopsy, several non-invasive approaches have been developed and validated to define NAFLD and evaluate NAFLD-associated diseases. Presently, NAFLD has been identified as an important and independent risk factor for developing several extrahepatic diseases, including atherosclerosis, cardiovascular disease (CVD), diabetes, and dementia. This review discusses current findings of up-to-date literature regarding the effects of NAFLD on the risk of atherosclerosis and CVD in Asia along with potential underlying biological mechanisms and therapeutic approaches to lower the NAFLD-related CVD risk. We further focus on the difference between NAFLD and metabolic dysfunction-associated fatty liver disease (MAFLD) on the risk of CVD and its implication by comparing the risk of NAFLD and MAFLD.

Antioxidant action of xanthine oxidase inhibitor febuxostat protects the liver and blood vasculature in SHRSP5/Dmcr rats

BACKGROUND

Xanthine oxidase (XO) generates reactive oxygen species during uric acid production. Therefore, XO inhibitors, which suppress oxidative stress, may effectively treat non-alcoholic steatohepatitis (NASH) and atherosclerosis via uric acid reduction. In this study, we examined the antioxidant effect of the XO inhibitor febuxostat on NASH and atherosclerosis in stroke-prone spontaneously hypertensive 5 (SHRSP5/Dmcr) rats.

METHODS

SHRSP5/Dmcr rats were divided into three groups: SHRSP5/Dmcr + high-fat and high-cholesterol (HFC) diet [control group, n = 5], SHRSP5/Dmcr + HFC diet + 10% fructose (40 ml/day) [fructose group, n = 5], and SHRSP5/Dmcr + HFC diet + 10% fructose (40 ml/day) + febuxostat (1.0 mg/kg/day) [febuxostat group, n = 5]. Glucose and insulin resistance, blood biochemistry, histopathological staining, endothelial function, and oxidative stress markers were evaluated.

RESULTS

Febuxostat reduced the plasma uric acid levels. Oxidative stress-related genes were downregulated, whereas antioxidant factor-related genes were upregulated in the febuxostat group compared with those in the fructose group. Febuxostat also ameliorated inflammation, fibrosis, and lipid accumulation in the liver. Mesenteric lipid deposition decreased in the arteries, and aortic endothelial function improved in the febuxostat group.

CONCLUSIONS

Overall, the XO inhibitor febuxostat exerted protective effects against NASH and atherosclerosis in SHRSP5/Dmcr rats.

Gut microbiota induces hepatic steatosis by modulating the T cells balance in high fructose diet mice

Metabolic diseases are often associated with high fructose (HF) consumption. HF has also been found to alter the gut microbiota, which then favors the development of nonalcoholic fatty liver disease. However, the mechanisms underlying of the gut microbiota on this metabolic disturbance are yet to be determined. Thus, in this study, we further explored the effect the gut microbiota concerning the T cells balance in an HF diet mouse model. We fed mice 60% fructose-enriched diet for 12 weeks. At 4 weeks, HF diet did not affect the liver, but it caused injury to the intestine and adipose tissues. After 12 weeks, the lipid droplet aggregation was markedly increased in the liver of HF-fed mice. Further analysis of the gut microbial composition showed that HF decreased the Bacteroidetes/Firmicutes ratio and increased the levels of Blautia, Lachnoclostridium, and Oscillibacter. In addition, HF can increase the expression of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) in the serum. T helper type 1 cells were significantly increased, and regulatory T(Treg) cells were markedly decreased in the mesenteric lymph nodes of the HF-fed mice. Furthermore, fecal microbiota transplantation alleviates systemic metabolic disorder by maintaining liver and intestinal immune homeostasis. Overall, our data indicated that intestinal structure injury and intestinal inflammation might be early, and liver inflammation and hepatic steatosis may be a subsequent effect following HF diets. Gut microbiota disorders impairing the intestinal barrier function and triggering immune homeostasis imbalance may be an importantly responsible for long-term HF diets induced hepatic steatosis.

Hepatic but not Intestinal FBP1 Is Required for Fructose Metabolism and Tolerance

Fructose intolerance in mammals is caused by defects in fructose absorption and metabolism. Fructose-1,6-bisphosphatase 1 (FBP1) is a key enzyme in gluconeogenesis, and its deficiency results in hypoglycemia as well as intolerance to fructose. However, the mechanism about fructose intolerance caused by FBP1 deficiency has not been fully elucidated. Here, we demonstrate that hepatic but not intestinal FBP1 is required for fructose metabolism and tolerance. We generated inducible knockout mouse models specifically lacking FBP1 in adult intestine or liver. Intestine-specific deletion of Fbp1 in adult mice does not compromise fructose tolerance, as evidenced by no significant body weight loss, food intake reduction, or morphological changes of the small intestine during 4 weeks of exposure to a high-fructose diet. By contrast, liver-specific deletion of Fbp1 in adult mice leads to fructose intolerance, as manifested by substantial weight loss, hepatomegaly, and liver injury after exposure to a high-fructose diet. Notably, the fructose metabolite fructose-1-phosphate is accumulated in FBP1-deficient liver after fructose challenge, which indicates a defect of fructolysis, probably due to competitive inhibition by fructose-1,6-bisphosphate and may account for the fructose intolerance. In conclusion, these data have clarified the essential role of hepatic but not intestinal FBP1 in fructose metabolism and tolerance.

A phase 2a, randomized, double-blind, placebo-controlled, three-arm, parallel-group study to assess the efficacy, safety, tolerability and pharmacodynamics of PF-06835919 in patients with non-alcoholic fatty liver disease and type 2 diabetes

AIM

To assess the safety, tolerability and pharmacodynamics (PD) of the ketohexokinase inhibitor PF-06835919 in participants with non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2D).

MATERIALS AND METHODS

This double-blind, placebo-controlled, parallel-group study enrolled adults with NAFLD (≥ 8% whole liver fat [WLF] using MRI proton density fat fraction [MRI-PDFF]) and T2D on stable doses of metformin (≥ 500 mg/day). Participants received once-daily placebo, PF-06835919 150 or 300 mg for 16 weeks. Randomization (1:1:1) was via an interactive response technology system. Endpoints included percentage change from baseline (CFB) in WLF using MRI-PDFF (primary endpoint) and CFB in HbA1c (co-primary endpoint) at 16 weeks, PD, safety and tolerability.

RESULTS

Among 164 participants randomized and treated, 145 completed the treatment (placebo, n = 50; PF-06835919 150 mg, n = 46; PF-06835919 300 mg, n = 49). At week 16, least squares mean (90% confidence interval) percentage CFB in WLF was -5.26% (-12.86%, 2.99%), -17.05% (-24.01%, -9.46%) and -19.13% (-25.51%, -12.20%) in the placebo, PF-06835919 150-mg and 300-mg groups, respectively (PF-06835919 300-mg group vs. placebo, P = .0288). Modest numerical reductions in HbA1c were observed in all groups that did not reach statistical significance. Treatment-emergent adverse event incidence was similar across groups (40.7%, 45.5% and 32.7% in the placebo, PF-06835919 150-mg and 300-mg groups, respectively), with no apparent dose-related trend.

CONCLUSIONS

PF-06835919 administration over 16 weeks was generally safe and well tolerated and resulted in reductions in WLF in participants with NAFLD and T2D.

Rare Sugar Metabolism and Impact on Insulin Sensitivity along the Gut-Liver-Muscle Axis In Vitro

Rare sugars have recently attracted attention as potential sugar replacers. Understanding the biochemical and biological behavior of these sugars is of importance in (novel) food formulations and prevention of type 2 diabetes. In this study, we investigated whether rare sugars may positively affect intestinal and liver metabolism, as well as muscle insulin sensitivity, compared to conventional sugars. Rare disaccharide digestibility, hepatic metabolism of monosaccharides (respirometry) and the effects of sugars on skeletal muscle insulin sensitivity (impaired glucose uptake) were investigated in, respectively, Caco-2, HepG2 and L6 cells or a triple coculture model with these cells. Glucose and fructose, but not l-arabinose, acutely increased extracellular acidification rate (ECAR) responses in HepG2 cells and impaired glucose uptake in L6 cells following a 24 h exposure at 28 mM. Cellular bioenergetics and digestion experiments with Caco-2 cells indicate that especially trehalose (α1-1α), D-Glc-α1,2-D-Gal, D-Glc-α1,2-D-Rib and D-Glc-α1,3-L-Ara experience delayed digestion and reduced cellular impact compared to maltose (α1-4), without differences on insulin-stimulated glucose uptake in a short-term setup with a Caco-2/HepG2/L6 triple coculture. These results suggest a potential for l-arabinose and specific rare disaccharides to improve metabolic health; however, additional in vivo research with longer sugar exposures should confirm their beneficial impact on insulin sensitivity in humans.

High Fructose Causes More Prominent Liver Steatohepatitis with Leaky Gut Similar to High Glucose Administration in Mice and Attenuation by Lactiplantibacillus plantarum dfa1

High-sugar diet-induced prediabetes and obesity are a global current problem that can be the result of glucose or fructose. However, a head-to-head comparison between both sugars on health impact is still lacking, and Lactiplantibacillus plantarum dfa1 has never been tested, and has recently been isolated from healthy volunteers. The mice were administered with the high glucose or fructose preparation in standard mouse chaw with or without L. plantarum dfa1 gavage, on alternate days, and in vitro experiments were performed using enterocyte cell lines (Caco2) and hepatocytes (HepG2). After 12 weeks of experiments, both glucose and fructose induced a similar severity of obesity (weight gain, lipid profiles, and fat deposition at several sites) and prediabetes condition (fasting glucose, insulin, oral glucose tolerance test, and Homeostatic Model Assessment for Insulin Resistance (HOMA score)). However, fructose administration induced more severe liver damage (serum alanine transaminase, liver weight, histology score, fat components, and oxidative stress) than the glucose group, while glucose caused more prominent intestinal permeability damage (FITC-dextran assay) and serum cytokines (TNF-α, IL-6, and IL-10) compared to the fructose group. Interestingly, all of these parameters were attenuated by L. plantarum dfa1 administration. Because there was a subtle change in the analysis of the fecal microbiome of mice with glucose or fructose administration compared to control mice, the probiotics altered only some microbiome parameters (Chao1 and Lactobacilli abundance). For in vitro experiments, glucose induced more damage to high-dose lipopolysaccharide (LPS) (1 µg/mL) to enterocytes (Caco2 cell) than fructose, as indicated by transepithelial electrical resistance (TEER), supernatant cytokines (TNF-α and IL-8), and glycolysis capacity (by extracellular flux analysis). Meanwhile, both glucose and fructose similarly facilitated LPS injury in hepatocytes (HepG2 cell) as evaluated by supernatant cytokines (TNF-α, IL-6, and IL-10) and extracellular flux analysis. In conclusion, glucose possibly induced a more severe intestinal injury (perhaps due to LPS-glucose synergy) and fructose caused a more prominent liver injury (possibly due to liver fructose metabolism), despite a similar effect on obesity and prediabetes. Prevention of obesity and prediabetes with probiotics was encouraged.

The Human Gut Virome and Its Relationship with Nontransmissible Chronic Diseases

The human gastrointestinal tract contains large communities of microorganisms that are in constant interaction with the host, playing an essential role in the regulation of several metabolic processes. Among the gut microbial communities, the gut bacteriome has been most widely studied in recent decades. However, in recent years, there has been increasing interest in studying the influences that other microbial groups can exert on the host. Among them, the gut virome is attracting great interest because viruses can interact with the host immune system and metabolic functions; this is also the case for phages, which interact with the bacterial microbiota. The antecedents of virome-rectification-based therapies among various diseases were also investigated. In the near future, stool metagenomic investigation should include the identification of bacteria and phages, as well as their correlation networks, to better understand gut microbiota activity in metabolic disease progression.

Dietary and nutrition considerations in caring for patients with nonalcoholic fatty liver disease: Updates for the practicing clinician

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease worldwide, affecting up to one-third of the global population. The disease is defined by excess fat deposition in the liver and has a strong correlation with metabolic syndrome, which, in turn, is also a risk factor for disease progression, including the development of steatohepatitis, advanced fibrosis, cirrhosis, and hepatocellular carcinoma. Although a number of medications are being explored for disease mitigation, nothing is currently approved, and the mainstay of therapy remains dietary and lifestyle intervention that promotes weight loss as well as management of comorbid conditions. The landscape that guides care for patients with NAFLD continues to evolve. Clinicians caring for these patients need to consider underlying disease state and nutrition risk in addition to concurrent related diagnoses, such as insulin resistance and hyperlipidemia, when formulating treatment plans. The following is a comprehensive review of the current dietary and nutrition considerations in the management of patients with NAFLD, with a special emphasis on implications for the practicing clinician.

Understanding NAFLD: From Case Identification to Interventions, Outcomes, and Future Perspectives

While non-alcoholic fatty liver disease (NAFLD) is a prevalent and frequent cause of liver-related morbidity and mortality, it is also strongly associated with cardiovascular disease-related morbidity and mortality, likely driven by its associations with insulin resistance and other manifestations of metabolic dysregulation. However, few satisfactory pharmacological treatments are available for NAFLD due in part to its complex pathophysiology, and challenges remain in stratifying individual patient's risk for liver and cardiovascular disease related outcomes. In this review, we describe the development and progression of NAFLD, including its pathophysiology and outcomes. We also describe different tools for identifying patients with NAFLD who are most at risk of liver-related and cardiovascular-related complications, as well as current and emerging treatment options, and future directions for research.

Prospects for the use of drugs from the group of agonists of glucagon-like peptide-1 receptors in the treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases. To a large extent, the development of this disease is associated with metabolic syndrome. There is a pathogenetic association of NAFLD with obesity, type 2 diabetes mellitus (DM2), cardiovascular diseases and chronic kidney disease. Numerous studies demonstrate that an increase in the incidence of NAFLD occurs in parallel with an increase in the prevalence of obesity and DM 2. A number of scientific studies in the field of medicine have made it possible to identify the main pathogenetic mechanisms of the development of the disease, as well as the possibility of using various pharmacological drugs to correct these conditions. Currently, the possibility of using in the future a group of drugs that have a single mechanism for controlling the development of hepatic steatosis, and further progression with the formation of inflammation, cirrhosis and, in some cases, hepatocellular carcinoma, is being considered. Of particular interest is a class of drugs intended for the treatment of type 2 diabetes and obesity – glucagon-like peptide-1 receptor agonists (arGLP-1). A search was made of clinical studies, meta-analyses, literature reviews in databases and registries of medical publications over a period of 10 years. Changes in anthropometric indications, changes in non-invasive markers of liver steatosis, inflammation and fibrosis, as well as histological data on the background of the use of drugs of the arGLP-1 class were studied. It has been demonstrated that the study drug class may have a significant potential for impact on NAFLD. However, further studies with sufficient duration and histological evaluation are needed to fully evaluate the effectiveness of arGLP-1 in the treatment of NAFLD.

A Comparison of Primary Human Hepatocytes and Hepatoma Cell Lines to Model the Effects of Fatty Acids, Fructose and Glucose on Liver Cell Lipid Accumulation

Non-alcoholic fatty liver disease (NAFLD) begins with lipid accumulation within hepatocytes, but the relative contributions of different macronutrients is still unclear. We investigated the impact of fatty acids, glucose and fructose on lipid accumulation in primary human hepatocytes (PHH) and three different cell lines: HepG2 (human hepatoblastoma−derived cell line), Huh7 (human hepatocellular carcinoma cell line) and McA-RH7777 (McA, rat hepatocellular carcinoma cell line). Cells were treated for 48 h with fatty acids (0 or 200 μM), glucose (5 mM or 11 mM) and fructose (0 mM, 2 mM or 8 mM). Lipid accumulation was measured via Nile Red staining. All cell types accumulated lipid in response to fatty acids (p < 0.001). PHH and McA, but not HepG2 or Huh7 cells, accumulated more lipid with 11 mM glucose plus fatty acids (p = 0.004, fatty acid × glucose interaction, for both), but only PHH increased lipid accumulation in response to fructose (p < 0.001). Considerable variation was observed between PHH cells from different individuals. Lipid accumulation in PHH was increased by insulin (p = 0.003) with inter-individual variability. Similarly, insulin increased lipid accumulation in both HepG2 and McA cells, with a bigger response in McA in the presence of fatty acids (p < 0.001 for fatty acid × insulin). McA were more insulin sensitive than either HepG2 or Huh7 cells in terms of AKT phosphorylation (p < 0.001 insulin × cell type interaction). Hence, glucose and fructose can contribute to the accumulation of lipid in PHH with considerable inter-individual variation, but hepatoma cell lines are not good models of PHH.

Naringin attenuates fructose-induced NAFLD progression in rats through reducing endogenous triglyceride synthesis and activating the Nrf2/HO-1 pathway

Background: Excessive fructose consumption causes hepatic lipid accumulation via increased triglyceride (TG) synthesis, leading to the development and progression of non-alcoholic fatty liver disease (NALFD). Naringin, a flavanone glycoside found in citrus fruit, has antioxidant and hypolipidemic properties. Therefore, the aim of this study was to investigate the effect of naringin on fructose-induced NAFLD in rats and the possible underlying mechanism. Methods: Male Sprague Dawley rats were given 10% (w/v) fructose in drinking water for 12 weeks. Naringin (100 mg/kg/day) was administered orally to rats for the last 4 weeks of fructose overload. After 12 weeks of treatment, the hepatic lipid content was determined. In addition, the expression of proteins involved in de novo lipogenesis (DNL) and TG synthesis as well as antioxidant and inflammatory mediators in the liver were examined by western blot analysis. Results: Treatment of fructose-fed rats with naringin significantly decreased the hepatic TG and cholesterol content as well as serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities. Naringin treatment also decreased the hepatic expression of carbohydrate response element binding protein (ChREBP), sterol regulatory element-binding protein-1c (SREBP-1c) and nuclear SREBP-1c (nSREBP-1c) as well as enzymes involved in DNL (acetyl CoA carboxylase [ACC] and fatty acid synthase [FAS]) and an enzyme involved in TG synthesis (glycerol-3-phosphate acyltransferase 1 [GPAT-1] and diacylglycerol acyltransferase2 [DGAT2]) in fructose-fed rats. In addition, naringin induced a significant decrease in the hepatic expression of nuclear factor kappa B (NF-κB) and tumor necrosis factor α (TNF-α). Furthermore, naringin administration restored the expression of the antioxidant mediators nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase-1 (HO-1) in the liver of fructose-fed rats. Conclusion: These results demonstrate that oral administration of naringin protects against fructose-induced hepatic steatosis by decreasing DNL and TG synthesis. In addition, naringin could prevent NAFLD progression via targeting the Nrf2/HO-1 and the NF-κB/TNF-α pathways.

Camel milk protein hydrosylate alleviates hepatic steatosis and hypertension in high fructose-fed rats

CONTEXT

Camel milk is used in traditional medicine to treat diabetes mellitus hypertension and other metabolic disorders.

OBJECTIVE

This study evaluated the antisteatotic and antihypertensive effects of camel milk protein hydrolysate (CMH) in high fructose (HF)-fed rats and compared it with the effects afforded by the intact camel milk protein extract (ICM).

MATERIALS AND METHODS

Adult male Wistar rats were divided into 6 groups (n = 8 each) as 1) control, 2) ICM (1000 mg/kg), 3) CMH (1000 mg/kg), 4) HF (15% in drinking water), 5) HF (15%) + ICM (1000 mg/kg), and 6) HF (15%) + CMH (1000 mg/kg). All treatments were given orally for 21 weeks, daily.

RESULTS

Both ICM and CMH reduced fasting glucose and insulin levels, serum and hepatic levels of cholesterol and triglycerides, and serum levels of ALT and AST, angiotensin II, ACE, endothelin-1, and uric acid in HF-fed rats. In addition, both ICM and CMH reduced hepatic fat deposition in the hepatocytes and reduced hepatocyte damage. This was associated with an increase in the hepatic activity of AMPK, higher PPARα mRNA, reduced expression of fructokinase C, SREBP1, SREBP2, fatty acid synthase, and HMG-CoA-reductase. Both treatments lowered systolic and diastolic blood pressure. However, the effects of CMH on all these parameters were greater as compared to ICM.

DISCUSSION AND CONCLUSIONS

The findings of this study encourage the use of CMH in a large-scale population and clinical studies to treat metabolic steatosis and hypertension.